ESOS Energy Audits

The Energy Savings Opportunity Scheme (ESOS) is the United Kingdom’s implementation of Article 8 (4 to 6) of the EU Energy Efficiency Directive (2021/27/EU). It requires all large UK companies to complete representative energy audits across their entire operations including buildings, transport and processes.  

The purpose of ESOS is to help organisations better understand how energy is used across their business, identify cost-effective energy saving opportunities, and improve long-term energy management. While ESOS is primarily a compliance requirement, many organisations also use the process to reduce operational costs, improve sustainability performance, and support wider ESG and decarbonisation initiatives.

ESOS Phase 4 applied to all large organisations in the UK.  

An organisation qualifies if it has: 

• More than 250 employees 

OR 

• Annual turnover of more than £44 million AND an annual balance sheet of more than £38 million 

ESOS also has a ‘One-in-all-in’ approach to corporate groups. Where at least one entity meets the qualification criteria, the whole corporate group must also participate in the ESOS regardless of company size. 

If you're unsure whether your organisation qualifies, our consultants can help assess your eligibility and determine the most efficient route to compliance. 

The qualification date is 31st December 2026 – where it is determined if your organisation meets the ESOS qualification criteria based on your last full set of company accounts.  

If your company qualifies for ESOS, you have until 5th December 2027 to complete the necessary energy audits. 

Many organisations already know that they qualify. Because energy audits completed between January 2023 and December 2027 can count toward ESOS Phase 4 compliance, organisations can begin audits early to spread costs, secure auditor availability, and avoid the compliance deadline rush. 

Following the ESOS audit compliance date, organisations are required to produce an Action Plan and submit annual progress reports every year on the 5th December through 2030.

Key changes introduced in ESOS Phase 4 include: 

• Action Plan Progress must now be included within the ESOS Assessment
• Organisations must explain where Action Plan commitments have not been achieved
• Display Energy Certificates (DECs) and Green Deal Assessment (GDAs) are no longer recognised compliance routes 
• There is no mandatory net-zero requirement for Phase 4

Although decarbonisation planning is voluntary, Antea Group includes practical decarbonisation recommendations within our ESOS energy audits at no additional cost. Because energy efficiency and greenhouse gas emissions are closely linked, this approach helps organisations identify opportunities that support both compliance and long-term sustainability objectives. 

While ESOS is a regulatory requirement, it also provides valuable opportunities to improve business performance. A well-executed ESOS assessment can help organisations: 

• Identify opportunities to reduce energy consumption and operating costs  
• Improve energy efficiency across buildings, transport, and processes  
• Support broader sustainability and decarbonisation goals  
• Prioritise energy-saving investments based on data  
• Strengthen ESG reporting and environmental performance  
• Meet compliance requirements while delivering long-term business value 

Our consultants provide end-to-end support throughout the ESOS compliance process. 

1. Determine Qualification 

We confirm whether your organisation meets the ESOS qualification criteria and identify which entities are in scope. 

2. Define the Compliance Scope 

We review your energy use across buildings, transport, and industrial processes to determine the most appropriate audit approach. 

3. Conduct Energy Audits 

Our ESOS Lead Assessors complete representative energy audits and identify practical opportunities to improve energy efficiency.

4. Prepare Compliance Documentation 

We compile the required findings, provide recommendations, and support your ESOS reporting requirements. 

5. Support Ongoing Compliance 

Where needed, we help develop Action Plans and support organisations with ongoing energy management and future compliance obligations. 

Our experienced ESOS Lead Assessors provide end-to-end compliance support, including: 

• Multiple in-house ESOS Lead Assessors 
• ESOS scoping to identify the most cost effective and beneficial route to compliance 
• Extrapolation of survey findings for your entire estate 
• Offer a variety of energy audits, including: 
  • Visual inspections 
  • Investment-grade building 
  • Thermographic surveys 
  • Environmental monitoring 
  • Transport audits  
• Detailed energy profiling  
• Utility bill analysis 
• Advanced audit methods 
• ISO5001 implementation support 
• Europe wide coverage – we have certified energy auditors across Europe meaning EU EED compliance in multiple countries can be achieved under a single contract. Local language, knowledge and culture is balanced with consistent reporting and recommendations. 

Our consultants bring hands‑on experience across sustainability, health and safety, and environmental management. We understand that energy is only one of the ESG topics that our clients are tackling alongside many more.  

Unlike providers who focus solely on regulatory compliance, we help clients identify opportunities where energy efficiency improvements can also deliver wider business benefits, including: 

• Reduced operating costs  
• Improved productivity  
• Greater employee comfort  
• Reduced absenteeism  
• More efficient operational processes 

Our experienced ESOS Lead Assessors have been supporting organisations since ESOS was first introduced, helping clients move beyond compliance to achieve measurable business value and stronger return on investment.

Through the Inogen Alliance, we have certified energy auditors across Europe.  

This means that by partnering with Antea Group, we can conduct local energy audits in each EU country in which you operate, under one single contract – therefore removing the need for managing multiple EED projects and contractors. We handle everything to ensure audits both meet the specific regulatory requirements of the member state, but that reporting is consistent and that findings are collated in a simplified manner for internal reporting.

Through the Inogen Alliance, we have certified energy auditors across Europe.

This means that by partnering with Antea Group, we can conduct local energy audits in each EU country in which you operate, under one single contract – therefore removing the need for managing multiple EED projects and contractors. We handle everything to ensure audits both meet the specific regulatory requirements of the member state, but that reporting is consistent and that findings are collated in a simplified manner for internal reporting.